Process for the photomechanical production of single- or multicolor pictures or writing on hard material



Sept. 27, 1938. pRlNZ r AL 2,131,298

PROCESS FOR THE PHOTOMECHANICAL PRODUCTION OF SINGLE- OR MULTICOLOR PICTURES OR WRITING ON HARD MATERIAL I Filed Feb. 8, 1937 I lilvelzof,

'15 prising the originalto be copied, followed by the ing, of-a coloring matter consisting of a fluid disaid of a cotton-wool or similar soft pad. p ay d n to the den d layer n t 20 tedious and troublesome; the pressure exerted.- encythe outlines are ill-defined, and, in addition, the ny f h l y r mpl yed in the previous 1 Patented Se t.- 27, 1938 a v t I 2 131 UNITED STATES PATENT OFFICE PROCESS Fonfrna PHOTOMEOHANIOAL PRODUCTION OF sum on noun-.- A conolt PICTURES on. wlu'rmo on man Leopold Prinz, London, England; and l'aul Morgenstern, gonna, Austria, Minors to The p 0 Company Limited, London, England, a British company Application February a, 1937, SarlalNo; 124,738 ,In Austria February 13,1986

1 Claim. (01. 95-55) This invention relates a to' processes for the not proved possible hitherto to obtain satisfacphotomechanical production of singleor multitory results even by means of the spraying methcolor pictures or writing on hard material. 0d. Further, the known processes are attended I Numerous proposals have heretofore been made by the drawback that in the-course of develop- 5 for photomechanically producing singleor multiment in water or the subsequent treatment with 5 color pictures or writing on plates-orother arthe cotton-wool pad the-colors may readily be ticles of hard material, such as glass, Celluloid, emlldged- I I r or metal. In these processes there is first ap-- 'I'hepresent nvent on h s r i spbiect o P plied to the plate which is to be provided with vide an improved process for the photomechanl- 10 pi t r or itin ljght-hardenable oating cal production of singleor multi-color pictures 10 which. exhibits a' differential hardening on ex- 'or Writing on hard material, which obviates the posure to light consisting, for example, of a described drawbacks. chromate-albumen layer, after which this layer The inventi n c nsists p ma ily in the mp is exposed to light through a transparency comm o h Production the le Writapplicationof the respective color, The m persion of one or more powdered mineral pigand can be wiped oft the other places with'the eral pigments are I fast to light, and can be Known processes of this kind have a number 'm h above dlsperelon- I Will e DDr of drawbacks. Particularly, they are extremely elated that e p i n h nfl tedious since the colors dry only very slowly on layer leused herein to m an n h e lay r the light-hardenable layer. J This circumstance which exhibit a differential hardening on ex- 25 makes itself felt more particularly in the produc- POSuIe to light- 7 I tionof multi-color pictures or writing, in which, h P wde d mineral pi ments are preferably in the manner described, after the exposure of dw h about 0f printer's, ni h. the light-hardenable layer, first one color has of l: 1 1' 1 f lav nd r- Th s. ebeen applied, and then, after this color has dried 001111118 t0 th nvent n, he 0 1011118 matter -manually bymeans of the roller is not uniform Inleme es, n 1 m e'p lm utsi e 8- in I a at all points and, therefore, ill-defined outli the form of-ink, may be added to the mass for heretofore, likewise has the disadvantage'that min al c in mat r.

colors hitherto found to be suitable for the sprayprocesses may be used as the light-hardenable ing method, for example aniline. dyes, are not alayer, p e e ab te-a men aye It ways fast to light. The majority 01' colors'cahas now been found that it is possible, when using pable of -being sprayed attack the chromate-alpowdered mineral pi ments. toprovide a light- 5 bumen layer, or destroy itinparts, so that it has hardenable layer of such composition that the 66 a i lines could not be coming smudged time required for drying v by the addition of a 15% alum solution to the chromate-albumen solution before application to the material. The powdered mineral pigment is thereby rapidly absorbed, with the result 'that the time required for drying is very much reduced. Further, it has been found that the addition of. alum to the light-hardenable layer has the effect oi making the colors harder, the latter are not impaired in any way in the course of the development in water and also do not tend to become smudged in the course of the usual treatment with the cotton wool pad. The term development" refers to the step of rendering the image visible by removal of unhardened parts of the exposed light-sensitive layer by washing with water. Rapidity of drying is thus achieved in the case of the invention by two means, namely byan addition of alum to the light-hardenable coating, and by an addition of petrol to the powdered mineral pigments.

The invention further provides of obtaining multi-color reproductions simpler manner than hitherto, ample, by spraying on several colors simultaneously, if they are spaced apart, or in succession with the employment of stencils or masks. The application by spraying of a plurality of colors by means of stencils is known in the production the possibility in afar of signs whenthe colors are applied directly, 1. e.

without the employment of a light-hardenable layer. In the photomechanical processes to which the present invention relates, spraying by means of stencils has not been carried out heretofore. for the reason that in'consequence of the colors hitherto employed for this purpose, sharp outobtained by means .of a spraythe aid of stencils. It is only of powdered mineral ing process with a through the employment pigments in the above-mentioned admixtures that it becomes possible to spray a plurality of colors with the aid of stencils.

individual colors are thereby prevented from beor blurred, or the outlines from running into one another during development.

Copies obtained by the new process may be employed as advertisement signs, makers nameplates and output-plates, scales more particularly for wireless sets for which high demands are made as regards sharpness of outline, watch and clock glasses, advertising mirrors, and other advertisement plates, translucent. writing on mirrors, transparencies, etc., and the process may be carried out on any hard material, such as glass, metal, Celluloid, wood and the like. Two examples of improved articles of manufacture according to the invention are diagrammatically illustrated in the accompanying drawing, wherein:-

Figure 1 is a plan view of an advertising plaque, and

Figure 2 is a section taken on the line 2-2 in Figure Lbutonanenlargedscale;

is very considerably reduced. This is achieved ered by a picture, figure, lettering namely, for expowder diflerent colors. The

Figure 3 is a plan view showing part of a station indicator of a radio-receiving set.

Referring first to Figures 1 and 2, an advertising plaque comprises a sheet or plate of glass Ill provided on the rear facewith a black legend i2 and a multicolor picture whereof the parts I are red and the parts l6 are black. The parts l2, l4 and i6 constituting the legend and picture may consist of powdered mineral pigment in a varnish, or in a mixture of varnish and lavender oil, provided as described above. A background ll constituted by a gold or yellow ground coating is provided on the back of the plaque by spraying and forms a protective covering which, however, in some cases may be omitted, especially when it is desired that those parts of the plaque not covor the like shall be transparent. In Figure 2 the thickness of the layers i2, i4, i6, i8 is exaggerated for the sake of clearness.

As one example of colored sprayable mass that may be employed, 1 lb. maycontain 58% mineral The ink serves for modifying the color or tone of the powdered mineral pigment that is employed, and in some cases may be omitted.

Referring. to Figure 3, the station indicator consists of a sheet or plate of glass Ill having three wave-length scales 2!, 2|, 28 with which the names of stations 23,. 25 and 21 are respectively associated. Each scale and its associated legends are shown ample green, black and red, as indicated in the drawing. No protective coating or colored ground is provided on this indicator in order that it may be almost wholly transparent.

We claim:

A process for of multi-color pictures or legends rial, comprising the steps of exposing to light through a nsparency comprising an original to be copied, a light-hardenable coating on the hard material'that contains alum in solution and exhibits a differential hardening on exposure to light, spraying a plgality of powdered mineral pigments with the d of stencils, one for each color, which pigments are each dispersed in a fluid medium comprising approximately 10% of printers varnish, 30% of a readily volatile liquid and 2%0! oil of lavender, dusting the exposed coating withtalcum powder after the, colored fluid medium has been applied thereto, developing the dried colored exposed'coating by removing its unhardened parts by washing with water, and removing surplus coloring matter from the developed coating.

the photomechanical production on hard mate- LEOPOLD PRINZ. PAUL MORGENBI'ERN pigment, 30% petrol, 2% oil and 10% ink. The

approximate weight of the ingredients may be:-

. Ounces Mineral pigment l 9.30

Peta-0L; 4.8 nu 3o T'nlr LG 

